<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<!-- 
Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

 http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License. 
-->
<html>
<head>
    <link type="text/css" rel="stylesheet" href="https://struts.apache.org/css/default.css">
    <style type="text/css">
        .dp-highlighter {
            width:95% !important;
        }
    </style>
    <style type="text/css">
        .footer {
            background-image:      url('https://cwiki.apache.org/confluence/images/border/border_bottom.gif');
            background-repeat:     repeat-x;
            background-position:   left top;
            padding-top:           4px;
            color:                 #666;
        }
    </style>
    <link href='https://struts.apache.org/highlighter/style/shCoreStruts.css' rel='stylesheet' type='text/css' />
    <link href='https://struts.apache.org/highlighter/style/shThemeStruts.css' rel='stylesheet' type='text/css' />
    <script src='https://struts.apache.org/highlighter/js/shCore.js' type='text/javascript'></script>
    <script src='https://struts.apache.org/highlighter/js/shBrushPlain.js' type='text/javascript'></script>
    <script src='https://struts.apache.org/highlighter/js/shBrushXml.js' type='text/javascript'></script>
    <script src='https://struts.apache.org/highlighter/js/shBrushJava.js' type='text/javascript'></script>
    <script src='https://struts.apache.org/highlighter/js/shBrushJScript.js' type='text/javascript'></script>
    <script src='https://struts.apache.org/highlighter/js/shBrushGroovy.js' type='text/javascript'></script>
    <script src='https://struts.apache.org/highlighter/js/shBrushBash.js' type='text/javascript'></script>
    <script type="text/javascript">
        SyntaxHighlighter.defaults['toolbar'] = false;
        SyntaxHighlighter.all();
    </script>
    <script type="text/javascript" language="javascript">
        var hide = null;
        var show = null;
        var children = null;

        function init() {
            /* Search form initialization */
            var form = document.forms['search'];
            if (form != null) {
                form.elements['domains'].value = location.hostname;
                form.elements['sitesearch'].value = location.hostname;
            }

            /* Children initialization */
            hide = document.getElementById('hide');
            show = document.getElementById('show');
            children = document.all != null ?
                    document.all['children'] :
                    document.getElementById('children');
            if (children != null) {
                children.style.display = 'none';
                show.style.display = 'inline';
                hide.style.display = 'none';
            }
        }

        function showChildren() {
            children.style.display = 'block';
            show.style.display = 'none';
            hide.style.display = 'inline';
        }

        function hideChildren() {
            children.style.display = 'none';
            show.style.display = 'inline';
            hide.style.display = 'none';
        }
    </script>
    <title>Alt Syntax</title>
</head>
<body onload="init()">
<table border="0" cellpadding="2" cellspacing="0" width="100%">
    <tr class="topBar">
        <td align="left" valign="middle" class="topBarDiv" align="left" nowrap>
            &nbsp;<a href="alt-syntax.html">Alt Syntax</a>
        </td>
        <td align="right" valign="middle" nowrap>
            <form name="search" action="https://www.google.com/search" method="get">
                <input type="hidden" name="ie" value="UTF-8" />
                <input type="hidden" name="oe" value="UTF-8" />
                <input type="hidden" name="domains" value="" />
                <input type="hidden" name="sitesearch" value="" />
                <input type="text" name="q" maxlength="255" value="" />
                <input type="submit" name="btnG" value="Google Search" />
            </form>
        </td>
    </tr>
</table>

<div id="PageContent">
    <div class="pageheader" style="padding: 6px 0px 0px 0px;">
        <!-- We'll enable this once we figure out how to access (and save) the logo resource -->
        <!--img src="/wiki/images/confluence_logo.gif" style="float: left; margin: 4px 4px 4px 10px;" border="0"-->
        <div style="margin: 0px 10px 0px 10px" class="smalltext">Apache Struts 2 Documentation</div>
        <div style="margin: 0px 10px 8px 10px"  class="pagetitle">Alt Syntax</div>

        <div class="greynavbar" align="right" style="padding: 2px 10px; margin: 0px;">
            <a href="https://cwiki.apache.org/confluence/pages/editpage.action?pageId=13974">
                <img src="https://cwiki.apache.org/confluence/images/icons/notep_16.gif"
                     height="16" width="16" border="0" align="absmiddle" title="Edit Page"></a>
            <a href="https://cwiki.apache.org/confluence/pages/editpage.action?pageId=13974">Edit Page</a>
            &nbsp;
            <a href="https://cwiki.apache.org/confluence/pages/listpages.action?key=WW">
                <img src="https://cwiki.apache.org/confluence/images/icons/browse_space.gif"
                     height="16" width="16" border="0" align="absmiddle" title="Browse Space"></a>
            <a href="https://cwiki.apache.org/confluence/pages/listpages.action?key=WW">Browse Space</a>
            &nbsp;
            <a href="https://cwiki.apache.org/confluence/pages/createpage.action?spaceKey=WW&fromPageId=13974">
                <img src="https://cwiki.apache.org/confluence/images/icons/add_page_16.gif"
                     height="16" width="16" border="0" align="absmiddle" title="Add Page"></a>
            <a href="https://cwiki.apache.org/confluence/pages/createpage.action?spaceKey=WW&fromPageId=13974">Add Page</a>
            &nbsp;
            <a href="https://cwiki.apache.org/confluence/pages/createblogpost.action?spaceKey=WW&fromPageId=13974">
                <img src="https://cwiki.apache.org/confluence/images/icons/add_blogentry_16.gif"
                     height="16" width="16" border="0" align="absmiddle" title="Add News"></a>
            <a href="https://cwiki.apache.org/confluence/pages/createblogpost.action?spaceKey=WW&fromPageId=13974">Add News</a>
        </div>
    </div>

    <div class="pagecontent">
        <div class="wiki-content">
            <div id="ConfluenceContent">

<p>The <em>altSyntax</em> is an option that can be defined in <a shape="rect" href="strutsproperties.html">struts.properties</a>. By default it is set to true and it is <strong>strongly</strong> recommend you do not change that unless you are upgrading from WebWork 2.1.7 or previous versions.</p>

<div class="confluence-information-macro confluence-information-macro-tip"><p class="title">Migration tip</p><span class="aui-icon aui-icon-small aui-iconfont-approve confluence-information-macro-icon"></span><div class="confluence-information-macro-body"><p>You can also turn on the altSyntax on a per-page basis by using the <a shape="rect" href="set.html">set</a> tag. Simply set the name <em>useAltSyntax</em> to the value <em>true</em>. From this point on, all tags will use the altSyntax for the rest of the request.</p></div></div>

<p>The altSyntax changes the behavior of how tags are interpreted. Instead of evaluating each tag parameter against the value stack and needing single quotes to mark string literals, only marked expressions are evaluated.</p>

<p>Example:</p>

<p>the following code uses the <a shape="rect" href="tag-syntax.html">Tag Syntax</a>:</p>
<div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<pre class="brush: java; gutter: false; theme: Default" style="font-size:12px;">
&lt;s:iterator value="cart.items"&gt;
   ...
   &lt;s:textfield label="'Cart item No.' + #rowstatus.index + ' note'" 
                 name="'cart.items[' + #rowstatus.index + '].note'" 
                 value="note" /&gt;
&lt;/s:iterator&gt;
</pre>
</div></div>

<p>this is somewhat counter intuitive to normal HTML tag behaviour, and you get loads of single quotes. Now the same example in altSyntax:</p>

<div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<pre class="brush: java; gutter: false; theme: Default" style="font-size:12px;">
&lt;s:iterator value="cart.items"&gt;
   ...
   &lt;s:textfield label="Cart item No. %{#rowstatus.index} note" 
                 name="cart.items[%{#rowstatus.index}].note" 
                 value="%{note}" /&gt;
&lt;/s:iterator&gt;
</pre>
</div></div>

<p>Only expressions enclosed with %{} are evaluated. The code is shorter and clearer, very similar to JSTL EL usage. Quoting problems, eg. with javascript function calls, are avoided.</p>

<p>In order to fully understand why this option exists and what the differences are, it is best to get a bit of history about WebWork.</p>

<div class="confluence-information-macro confluence-information-macro-note"><span class="aui-icon aui-icon-small aui-iconfont-warning confluence-information-macro-icon"></span><div class="confluence-information-macro-body"><p>If you are <em>not</em> upgrading from WebWork 2.1.7 or previous versions and you don't care about the history of WebWork's evolution, you can skip this section. See the <a shape="rect" href="tag-syntax.html">Tag Syntax</a> section for more information on the standard tag syntax support</p></div></div>

<h1 id="AltSyntax-History">History</h1>

<p>In WebWork 2.1.4, the altSyntax option was introduced. The book, WebWork in Action, while based around WebWork 2.1.7, was entirely written with the assumption that the altSyntax was enabled. As of WebWork 2.2, the altSyntax is turned on by default and eventually the old syntax will no longer be supported and will be removed from the code.</p></div>
        </div>

        
    </div>
</div>
<div class="footer">
    Generated by CXF SiteExporter
</div>
</body>
</html>
